Can a large hiatal hernia develop a smal hard knot eel in the distended adbominal area that burns and is painful to gentle touch? is this ok?

No: This sounds like you have a different type of hernia or hernia plus abscess. This can be life threatening. Please get checked immediately. Go to an er if you have to but get checked.

(K)NotUrHiatalHernia: A hiatal hernia is an enlargement of the normal opening in your diaphragm thru which the esophagus passes; it is internal and nonpalpable. The knot you are describing may be an abdominal wall (ventral) hernia (especially if it's in the midline, at belly button or upper abdomen). I recommend you see your primary care doctor for an examination of this "knot".